Why excactly is the USB 3.0 performance so underwhelming on X79 boards??
The performance is based on the drive used for testing, too, so it could just be that. The lowest result and highest result from over the last year shows about 8 MB of difference using the same drive, with the same data on it.
That said, the ECS X79 board gave the best result I've seen so far. The ASUS was a bit underwhelming. The Gigabyte board is like right between the other two. That said, there's only about .75% difference between the three X79 Express products. Minor.
X79 Express introduces this USB SuperSpeed stuff...but they all seem to use far different controllers for what seem to be the same technology...I'm not sure who designed USB SuperSpeed directly, as it seems to be like JEDEC for memory, where several OEMs work together to develop the technology, and becuase of the many different controllers, obviously results will vary.
Of course, part of USB 3.0 interface is the driver. This is critical in USB 3.0 SuperSpeed...ultimately, I think it's the drivers that make or break a result. As far as I know, USB 3.0 doesn't even work in Windows XP properly.
The ECS board used a Texas Instruments controller, this Gigabyte board uses Fresco controllers, and the ASUS was a weird mix that I couldn't quite figure out, as there was 3 controllers, capable of 8 ports, but only six ports active.
Anyway, it's clear the results vary so much because of the different controllers. Whether it's the controller itself, the driver, or some weird hardware issue, I am not 100% sure, but I did expect the TI controller to be the fastest, and it was. I'm not sure what conclusions you want to draw from al lfo that, but USB 3.0 performance is not something I consider the fault of the board maker, as they are not responsible for driver development. They merely buy the parts.